水頭症を合併した頚髄神経鞘腫の1例

Cervical Spinal Neurilemmoma Associated with Hydrocephalus : Case Report

　抄録：頚髄腫瘍が水頭症の原因であった症例を経験した．症例は81歳，男性．頚部痛で発症し，MRIでC2-3高位に腫瘍性病変を認めた．初診後2週頃より歩行障害，尿失禁，痴呆症状が出現し，急速に進行した．頭部CTにて脳室拡大を認めたため，脊髄腫瘍に合併した水頭症と診断し，腫瘍摘出術を行った．腫瘍の病理学的所見は神経鞘腫であった．術中採取した髄液の蛋白量は286mg/dlであった．術後早期より水頭症の症状は改善し，術後3週の頭部CTでは術前に比べ脳室の縮小がみられた．脊髄腫瘍に合併して水頭症が発症することは脳神経外科や神経内科領域ではよく知られているが，整形外科における認識度は低い．脊髄腫瘍の経過観察中に，本症に特有の痴呆症状や歩行障害が出現した場合，早急に水頭症の検索を行う必要がある．また，水頭症を合併する脊髄腫瘍は，胸腰椎移行部以下での発生が多数を占め，頚髄神経鞘腫の報告は本例を含め6例のみである．

　This is a report of a case of spinal tumor associated with hydrocephalus. An 81-year-old male came to our hospital complaining of neck pain. An MRI scan revealed a mass in the region of the second and third cervical vertebrae. Three weeks after the initial visit, a gait disturbance, urinary incontinence, and dementia developed and rapidly progressed. A computed tomography (CT) scan showed enlargement of the cerebral ventricles. After diagnosing hydrocephalus secondary to the spinal tumor, the tumor was excised. The patient's CSF protein level was elevated to 286mg/dl at the time of the operation, and the pathological diagnosis of the tumor was neurilemmoma. The patient rapidly recovered from all symptoms postoperatively, and a CT scan 3 weeks after the operation revealed a reduction in ventricular size. Spinal tumors accompanied by hydrocephalus are well known by neurosurgeons, but since they are poorly recognized by orthopaedic surgeons in Japan, diagnosing hydrocephalus may be difficult when a patient with a spinal tumor suddenly develops incontinence and dementia. The majority of spinal tumors complicated by hydrocephalus have been located below the thoracolumbar junction. Cases of cervical nuerilemmoma associated with hydrocephalus are rare, and only 5 cases, including our own, have been reported. We conclude that hydrocephalus should be ruled out whenever a patient with a spinal tumor suddenly develops a gait disturbance, incontinence, and dementia.